Local: Cyanic acid
(the isomer of fulminic acid) is an unstable (explosive), poisonous, volatile,
clear liquid with the structure of H-O-C¡ÕN (the oxoacid formed from the
pseudohalogen cyanide), which is readily converted to
cyamelide and fulminic
acid. There is another isomeric cyanic acid with the
structure of H-N=C=O, called isocyanic acid. Cyanate group (and isocyanate group) can react with itself.
Cyanuric acid (also called pyrolithic acid), white monoclinic crystal with
the structure of [HOC(NCOH)2N], is the trimer
of cyanic acid. The
trimer
of isocyanic acid
is called biuret.

Cyanic acid:
H-N=C=O
or H-O-C¡ÕN

Fulminic acid: (H-C=N-O)
or H-C¡ÕN-O

Isocyanic acid:
H-N=C=O

Cyanuric acid:
HOC(NCOH)2N

Biuret:(NH2)CO)2 NH

Cyanic acid hydrolyses to ammonia and carbon dioxide in
water.

Cyanamide, the amide of normal cyanic acid, is
a white crystals melting at 45 C; readily soluble in water, alcohol
and ether. It is prepared commercially by carbide process from carbonate derived from limestone or
by the desulphurization of thiourea in the presence
of catalyst (mercuric oxide). It is prepared also by the action of ammonia with cyanogen halides.
It polymerizes to dicyandiamide when heated over 150 C
and to tricyantriamide as well as to melamine. Its metal
salt especially calcium cyanamide is an environmentally friendly
multi-purpose fertilizer which
reacts with water to release ammonia and calcium
carbonate to
supply nitrogen and lime to plants and soil.The commercial calcium cyanamide
contains about 65% calcium cyanamide, which has nitrogen 20 - 24% w/w. It
acts also as a defoliant, herbicide, soil insecticide,
and weed killer.
Its consumption as a fertilizer has been reduced. It is added to pig iron to impart nitrogen and
to desulfurize
steel. The reactivity of
the nitrile functional group in calcium cyanamide makes it as a chief industrial raw
material. It is used in the preparation of other products
include dicyandiamide, urea, thiourea,
and guanidine. It is used in the production of calcium
cyanide. Cyanide plays an important role in extracting precious metals.

Dicyandiamide is the dimer.
It is an
intermediate for melamine which us the basic ingredient of amino plastics and
resins. It is used in the
production of wide range of organic chemicals including slow
and continuous nitrogen
release fertilizers; fire proofing agent; epoxy
laminates for circuit boards, powder coatings and adhesives; water treatment
chemicals; dye fixing, leather and rubber chemicals; explosives;
pharmaceuticals. Dicyandiamide is also called cyanoguanidine.

Guanidine, also
called carbamidine, is a strongly alkaline and water-soluble compound,
NHC(NH2)2 It is formed by the oxidation of guanine in
urine as a normal product of protein metabolism in the body. In industry,
guanidine, containing nitrogens and N=C solid bond, and its modified
derivatives are versatile intermediates used in the manufacture of plastics,
resins, rubber chemicals, nitroguanidines (explosives), photo chemicals,
fungicides, and disinfectant. It has also biotechnological application of
protein separation, purification and as a protein denaturant. It can be
used as an oxygen scavenger to prevent corrosion
damage. It is used as a component of rocket propellants
because it produce a large amount of heat when
burned.